text: Ethanol molecules obtained after complete fermentation of the sugar coexists with 3 naturally monodeuterated isotopomers (CHD-CH-OH, CH-CHDOH and-CH-CHOD). Their presence can then be quantified with relative precision.
  On the following H-NMR spectrum (Figure 8), a peak corresponds to one of the three observed isotopomers of ethanol. 
  In the AOAC official method, the ratios of (D/H)CH and (D/H)CH are calculated by comparison with an Internal standard, tetramethylurea (TMU), with a certified (D/H) value.